Understand the electronic control composition and gas circuit system operating principles of the instrument, and quickly determine whether the instrument parameters and indicators are normal through daily diagnosis. Perform routine daily maintenance and periodic servicing in accordance with operating procedures to reduce the instrument failure rate.
1. Check Environmental Parameters
Upstream and downstream pressures shall be maintained at 0.083 MPa; carrier gas flow rate at 3 L/min; motive gas pressure at approximately 0.276 MPa. Plate current and grid current increase with rising radio frequency (RF) power. Dynamic changes of the above instrument parameters shall be monitored in real time.
Clean the dust filter when the pressure difference between upstream and downstream becomes excessive.
Abnormal backpressure indicates a gas leak.
Adjust the inlet pressure if the carrier gas flow rate is abnormal.
A plate current below 300 mA signifies incomplete sample combustion.
Increase the safety pressure of the motive gas regulator if the base frame lifts or lowers slowly.
2. System Leak Check
A leak check shall be performed every time maintenance is conducted on the analytical gas circuit or motive gas circuit. Three leak check methods are available: system leak check, segmented leak check, and motive gas leak check. The inspection result shall be either Pass or Fail.
If the system fails to pressurize, it indicates a severe leak in the analytical system or motive system causing pressurization failure. Inspect the seals of the automatic sweep burner head, combustion tube, and shrink valve tube for integrity.
If the pressure surges abruptly after system pressurization, it may be due to an unclosed valve allowing gas into the system or unstable infrared cell temperature. Close the faulty valve or stabilize the temperature.
If the pressure drops, it confirms a system leak; recheck all routine maintenance items.
3. Burnout of the Cleaning Assembly Spiral Head
After completion of sample analysis, the hot crucible and molten slag from the just-combusted sample may splash onto the spiral furnace head during cleaning, and the high-temperature slag melts part of the spiral head.
Solution:Open the selected Analysis Method, edit the Sample Cooling Time in its general parameters, and set the value from 0 s to approximately 5 s. This provides a cooling delay of about 5 seconds after analysis finishes and before the furnace base frame lowers, preventing the newly replaced spiral furnace head from being melted again.
